Interesting site..
They are actually LED displays?? LED's had only just come out then, i remember my uncle getting the first LED watch called the "Black Watch" - it late 70's and was ground breaking stuff.
Many of the European companies used a plastic PF coating, some were in fact a full resin sheet ( hasnt DDstoys got one of these?) with artwork screened on the underside.
We may knock the Playmatic games, but truth be known they were ahead of the USA companies in many ways, the use of LED displays is a prime example, only now that the HV displays are becoming redundant are LED displays being used and yet we think its really clever when someone makes these - LOL!!!! Rewind 30 years!
Im hoping to do a post of one particular European pinball manufacturer soon..... ill explain a lot more then